1. Field of the Invention
This invention relates to a system switch device which comprises a board switch, a display unit for displaying selected contents, and an electronic control unit for controlling terminal units according to the selected contents which are displayed through they key operations of the board switch.
2. Related Art
Recently, there have been strong demands for insuring safety in traveling a motor vehicle, improving comfortability inside it, and providing functions high in added value for it. In order to meet those demands, there is a tendency to install a number of electronic devices for processing vehicle data, external environmental data, man-machine data, external communications data, and other data. Those control devices mounted on a motor vehicle are intricate in arrangement, tending to be developed in technology.
It is necessary for the driver of the motor vehicle to transmit his wills or intentions quickly to those electronic devices while correctly judging driving conditions and environmental conditions from those variety of data. His wills or intentions are transmitted through switches. Accordingly, when those control units are installed on the vehicle, it is also necessary to install a number of switches on the dashboard. Those switches may be collected at one position by the following method: Switches are displayed on the screen of a CRT (cathode ray tube), and items in a menu are selected by touching the screen of the CRT, thereby to control, for instance, an audio device, and an air conditioner.
As was described above, in order to satisfy the variety of demands, it is necessary to install a number of electronic devices on the vehicle, and accordingly a number of switches must be arranged on the instrument board or the like. As the number of switches installed is increased, it becomes difficult for the driver to suitably operate all of the switches. On the other hand, it is necessary to improve the switches so that the driver's will is transmitted to the electronic devices with high efficiency.
The above-described method in which switches are displayed on the screen of a CRT, and for instance an audio device or an air conditioner is controlled merely by touching the screen of the CRT, suffers from the following difficulties: In the method, the switches are provided on the screen of the CRT. The CRT occupies a relatively large area for the CRT, and accordingly the provision of the CRT is limited in position. Furthermore, since the switches are integral with the display unit, the driver cannot operate the switches without changing his posture; more specifically, without turning his eyes. In addition, with the method, the driver is liable to use a lot of time for operating the switches during driving, which may adversely affect safety driving. Thus, the conventional method should be improved for safety driving.